Grinding-machine attachment.



Wm M4 J. S. WINGRANTZ. GRINDING MACHINE ATTACHMENT.

APPLICATION FILED MAY 13, 1914. I I 1,1 1 8,394. Patented Oct-13, 1914.

Illlullll .uuuwum I.

.'--:- m:-: MAL /A ail 1'? 3 WITNESSES INVE/NTOR ATTORNEY J. s. 11110111111121 GRINDING MACHINE ATTACHMENT. APPLICATION FILED MAY 13, 1914.

1 1 1 3,894. Patented 001.13, 1914.

2 SHEETS-SHEET 2.

WITNESSES INVENTOR UNI sTarrEs PATENT. OFFIQE:

' JOHN s. WINCRANTZ, or PITTSBURGH, EN-NSYLVA I'A, AssIGNon-ro sammnis.

NEWMAN," OF PITTSBURGH, PENNSYLVANIA.

. ennimiwe-mhcnmn arracrrmnivr.

7 To all whom it may concern a citizen of the U which all lost motion in the sliding wear =pa-i'ts is automatically taken up; the pro;-

Be it knownth t I, J OHN S. yVrNomN'rz,

'nited States, residing at Pittsburgh, in the county of Alleghenyand' State of Pennsylvania, hareinvented certain new and useful Improvements in Grinding- Machine Attachments, of which the follow v,ing is a specification.

The invention relates to attaclunents for use 111 connection with grinding machines.

such attachments being primarily intended. for use in grinding adzes and 'scythcs, The. -.invention has for its principal objects; the

provisionof an attachment which will se-.

curely. hold edzes of varioussizes and contours;-the provision of an attachment 1n vision of an attachment wherein improved means are provided for adjusting --the tool clamping bar; and. the pro'vlsion of improved mcnns upon the attachment and grinding machme whereby scythes (regardless of size and shape) are properly guided and supported with'respect to the grinding surface. .One embodiment 0f the invention is illustrated in the accompanying drawings;

wherein;

, Figure 1- is a front elevation of themachine' with a scythe and adz supported by the attachment and .in sect-ion, and Fig. 2

is a side elevation of the same attacl'unent with the adz and scythe blades shown in dot and dash lines. In the construction as illustrated in Figs.

. 1 andv 2, 1 is a grinding disk which is rotated from the handle 2, a train of gearing being interposed between, and lying n the casing 3; 4 is a conical grinding wheel which is.

mounted removably .upon the axle of the disk wheel in'any desired manner; and 5 1s a U-sha-ped bracket having a shank 6 secured detachably in position upon the ma chine by means of the set screw; 7, the

method of mounting the-bracket being one well luiown in the art.

Secured between the two upright arms 8 and 9 ,(Fig. 1) ofthe bracket 5 is a guide rod 10,"and mounted upon th s rodlC, for sliding and rocking movement, 15 the tool carryingframe 11. This frame 11 is adapt ed to carry the adv; 12 to be ground, the

blade of such adzfbeing securely clamped between the; fixed bottom bar 1?, und t g Specification 01 Letters Patent.- Patented Oct. 13 .1914.- Application filed m s, 1914. s ri inqieaaaoo. 3 I

movable clan iping bar-.1 4;. As indicated;

'Fig. 1, the'u per surfaceof the bar, is

preferabl'y made concave so that the blade 12 doesnot e'n 'age such bar at its left Till portion, but'orily adjacent its edges. .j Tli purpose of this feature of construction is to provide a' firm two-pointsupportfffor the lower side of the blade regardless: of ts contour, so that all blades, ranging'fi'om those much flatter upon the lower than the one fillfstrated to thosemucl re curved, will all be engaged by the at widely 'sepa ra ted po1nts, thus elimi' any tendency of the blade to 'rock'iipoliithe bar '13 such as would occur iftlie rot inided lower face of the blade touched its centra1,portion.'-

p The; ends of the;clamping' bar' 14?" are t guidedflpomthe "portions 15%16 at by mal ingthe ends ftirkeidas indie Y at- 17 in Figs. [1 ani 2, so that sucheir'sfpartially surroundt e upright bars 15 16.

As indicated in dotted lines in Figs.."1*iand.

2, the clamping bar 1; is made lJ-shapieid iii cross section, thus making the bar. l ghter and providing a, space for the cotter 18 (Fig.1) by means of which the. c ntntradthreaded, through the bar; 20 and wlii'ifh I bcar at their lower endsupo-n the ftopfsurface of the bar 14-. The advantage ncident a to the-use of the central swivel screw in con nection with the two sidescrews what are not swiveled will be readily apparent .l'f-

all t'hree screwswere swjivclcd, the "i ufil'ing of the bar 1?: back andllforth would" e a tedious operation, since"-'-the screws-firm;

necessarily have to'be adjusted orcr wed back in'unison, otherwise binding w'gult ddcur. The operator would therefore bdfoi' ed to shift from one screw tothe other. turning each nly a slight amount at one time. With the present arrangement each screw n be I prr tr-i-i 1,3,

Wi l- 'screw 19 1s threaded through h topdg'ai' ting "frame 11, such guidin .ecoomplidhd adjusted continuously to its extreme posi-' downwardly from the frame 11-are the rollers 23, such rollers having concave rims as.

indicated in Fig. 2 with such rims in engagement with the upper surface-of the guide bars 10. A similar roller 24 located between the rollers 23 engages the lower side of the guide bars '10, such roller being carried by the fork 25 projecting downwardly from the frame 11. This roller has its axle 26 slidable at each end in a slot 27, the two' sides of the fork 25 bein similar in this respect. I Beneath each end of the axle 26 of the roller is a spring 28, such spring in each case bearing at its upper end against-the axle and its other end bearing against a screw plug 29 whereby thetensionof the spring may be adjusted. It will be seen that the foregoing arrangement provides for a yielding engagement between the roller 24: and the lower side of the .bar 10. All lost motion due to wear between the rollers and the bar 10 is thus taken up, and any play. which would tend to permit the frame 11 to tilt sidewise, is eliminated. This arrangement is particularly advantageous in a machine of this character because of the large amount of gritty dust due to the grinding operation. This dust or dirt causes. rapid wear between sliding parts, and in the course of time an objectionable amount of play results. With the present arrangement this play is eliminated, and the blade 12 of the adz'is always hold in exact parallelism with the bar 10. Another advantage of'the construction resides in the fact that the rollers constitute antifriction means ermitting the guides to work casi ly along the bar 10, and

furthermore this arrangement involving the use of the rollers or wheels with the concave rims permlts the frame to .rock transversely of the rod. to bring the edge of the tool.

against the grinding disk or remove it therefrom.

When it is desired to grind a scythe the conical grinding wheel 4 is utilized. As indicated in Fig. 1, which shows a scythe 30 in cross section, all scythes are provided with a. rib 31, thus giving a recess 32 adjacent the side of the scythe opposite the cutting edge.

'. In order to support and guidetlie scythe the roller 33 is provided, such roller having a flange 34 engaging the recess 32 at the s de of the scythe. The engagement of this,

flange 34. w'ith the recess 32 prevents lateral movement of the scythe, there being sufiicient play, however, to permit the scythe to be moved longitudinally across the axis. of.

rotation of the grindin wheel ,LIhe bar 10 lying above the scyt e assists guiding it and giving it the proper angle for grinding', and also serves to prevent the accidental disengagement of the grooved edge of the scythe'from its supporting roller 33. The attachment permits of the accurate and convenient guiding of a scythe blade, without danger of inj ury to the blade or to the operator. The bar 10 not only serves to steady the blade and act as a guide therefor as the blade moves back and forth transversely of the bar and the wheel, but also prevents the blade from being turned at an improper angle, the relation of the roller and bar with respect to the grinding wheel 1 being such that when the edge of the blade engages the bar 10 it is at the proper angle with respect to the grinding wheel.

What I claim is:

1. In combination in a grinding machine having a grindin wheel, a guide extending transversely of .t e axis of rotation of the wheel, a tool carrying frame mounted slidably on the guide, a-movable clamping member guided at its ends on the frame, a screw threaded through the frame at the center of the clamp and swiveled thereto so as to move the clamp inboth directions, screws threaded through the frame on either side of the first screw and bearing against the clamp.

2. In combination in a grinding machine having a grinding wheel, a guide extending transversely of the axis of rotation of the wheel, a tool carrying frame mounted slidably on the guide and having a concave tool engaging surface whereby the tool to be ground is engaged on one side near its edges leaving the central portion out of engagement. and a clamp for engagipg the tool on its other face.

3. In combination in a grinding machine and other 1 having a grinding wheel, a guide extending transversely of the axis of rotation of the gagement therewith, the said antifriction' means being spring supported on one side of the said guide.

4. In combination in a grinding machine having a grinding wheel, a guide extending transversely of the axis of rotation of the wheel, a tool carrying framemounted on the guide, a. spring supported wheel carried by thefframe and engaging the lower side of the guide, and a .pair of wheels on the frame- .above the guide and engaging the guide on;

opposite si es of the first wheel.

5. In coirbination-in a grindingmachin'e having a grinding wheel, a round guide rod extending transversely of theaxis of rotation of the wheel, a tool carrying frame mounted on the rod, and rollerswlth coni cave bearing rims carried by the frame and engaging-the rod on the upper and; lower sides thereof fol-permitting the frame to I engaging the rod on the-upper and lower 1 HIUVO knigitndin'ally of the rotl and rock i sides thereof for permitting the frame to 1- transversely thereof. ilnove longitudinally of the rod and rock (3. ln r-mnbination in :i grinding niaehine i transversely 'thereof one of the said rollers 5 having a grinding wheel, 'a ronncl guide rmll being spring supported. extending transversely of the axis of rotal J OHN S. \VINCRANTZ. tion of the wheel, a tool carrying funnel \Vitnesses; mounted en the red, and rollers with eon- Ancr-nvonrn MARTIN, v

(are hearing rims carried by the frame and M.'L. JONES. 

